In conventional display devices or other electronic devices, a transparent glass substrate is usually selected as a substrate material. However, the trend of display devices and other electronic devices is towards lighter weights and thinner shapes while electronic products usage and the dependence increase with time. Therefore, a flexible display device (or another electronic device) having excellent properties such as mobility, flexibility, wearability, and impact resistance is further demanded. A flexible display device (or the other electronic device) containing TFTs can be manufactured by roll-to-roll process. The batch method for the TFTs can be manufactured by conventional equipment, and a transfer or release process is needed. The release process for the flexible substrate/glass substrate firstly forms TFTs on a flexible substrate attached onto the hard glass carrier. Thereafter, the flexible display device (or the flexible electronic device) is peeled from the hard glass carrier. If a plastic substrate is selected as the flexible substrate, it should meet the requirement of thermal resistance, size stability, and coefficient of thermal expansion. The plastic substrate and the hard glass carrier should have similar coefficient of thermal expansions, thereby avoiding deformation and warping of the plastic substrate during formation processes due to thermal mismatch of the plastic substrate and the hard glass carrier. Standard glass has a coefficient of thermal expansion of about 4 ppm/° C. A plastic substrate having a lower coefficient of thermal expansion close to that of the glass may reduce an interference stress problem caused from the coefficient of thermal expansion difference between the plastic substrate and the glass.
The disclosure provides a novel composition and corresponding processes of plastic films having a low thermal expansion difference and a high transmittance.